.458 RCM wildcat?

[WoodsQuest]

I got to thinking about a .458 wildcat built on an RCM case. After looking at the case dimensions it seems to me that necking up an RCM case to accept a .458 bullet would be possible. If a velocity of 2400fps could be attained that would give the rifle a MPBR of about 245yds when using the Barnes 300gr TTSX. With all the interest in .450 Bushmaster lately I thought it would be nice to have a similar cartridge in a standard short action. The biggest downfall of the .450 BM and .45 Raptor, to me, is the use of .451 bullets instead of .458.

I don’t know much about wildcatting or cartridge development, but I would think an RCM case could easily push a 300gr bullet to around 2400fps. Using an RCM case would optimize the round for a shorter barrel which to me, seems like it would belong on a bruiser of a cartridge like that. Anyone think this is possible?

 

[Millsworks]

Sounds like a plausible idea.
But I personally think you should be posting a question like this on a very different forum.
But someone here may chime in with some knowledge about this, possibly.

 

[MThuntr]

I know nothing of what you ask about the RCM parent cartridge however you could do a 458x2 American which is basically the 450 marlin using a very readily available belted magnum cartridge

 

[WoodsQuest]

The better question is who would want a rifle cartridge that launched a 300gr bullet at 2400fps for short range work? My guess is probably not many people because long range shooting seems to be the thing since the 6.5CM and RPRs hit the market. I just went through all my onX maps and did a bunch of distance measurements and most of my shooting ranges were well under 300yds, 240yds maximum. Just got me thinking about a high momentum, big, heavy slug, in a cartridge format.

 

[MThuntr]

I carry a 45-70 guide gun however a lot of places I hunt go from 50 yard visibility to 500 yard openings so it doesn't get as much attention as I had originally planned. I have a custom mold to cast some midweight (330 grains or so) .462 bullets designed for Marlin 45-70s that I really need to mess with...I'll powder coat them and then size them to .460 and shoot them hot.

 

[std7mag]

I say do it!
There is a reason Remington, and Savage jumped on the bandwagon that Ruger started.

I would have to look at ballistics, but it doesn't seem unreasonable in your velocities, dependant of course on barrel length.

Would this qualify for Indiana's cartridge restrictions?
May be why BM and such are .452.

 

[RUT JUNKEY]

I love my .458 SOCOM!! shoots awesome with the 300gr JHP.
....for Indiana, on public ground, must be .357 diameter with a min case length of 1.16in and max of 1.8in...on private ground, 1.16 and 3in...

 

[Ben Lamb]

You may have headspacing issues with a 458 RCM wildcat if you don't have a decent shoulder on the cartridge.

 

[1_pointer]

You may have headspacing issues with a 458 RCM wildcat if you don't have a decent shoulder on the cartridge.

Shoulder width is 0.516" so I think it should have enough shoulder to headspace. 'Twould be about the same difference between shoulder/neck on a 9.3X62.

 

[Ben Lamb]

Shoulder width is 0.516" so I think it should have enough shoulder to headspace. 'Twould be about the same difference between shoulder/neck on a 9.3X62.

There you go.

Could be a fun round to detach retinas & bruise shoulders.